APA引文

SpringerLink (Online service), Porro, G. B., & Maconi, G. (2007). Ultrasound of the gastrointestinal tract. Springer-Verlag Berlin Heidelberg.

芝加哥风格引文

SpringerLink (Online service), Gabriele Bianchi Porro, 与 Giovanni Maconi. Ultrasound of the Gastrointestinal Tract. Berlin, Heidelberg: Springer-Verlag Berlin Heidelberg, 2007.

MLA引文

SpringerLink (Online service), et al. Ultrasound of the Gastrointestinal Tract. Springer-Verlag Berlin Heidelberg, 2007.

警告:这些引文格式不一定是100%准确.